The invention discloses an image encryption method based on the projection synchronization of a hyperchaotic system. The method comprises the steps of plaintext image quantifying and ciphertext image quantifying. The first step comprises generating of a hyperchaotic sequence of a hyperchaotic driving system, image row scrambling, image column scrambling, image diffusing, circulation image row scrambling, image column scrambling, multiple rounds of image diffusing, and a ciphertext image is acquired. The second step comprises ciphertext image quantifying, generating of a hyperchaotic sequence of a hyperchaotic response system, time acquiring, column scrambling index and line scrambling index valuing, image inverse diffusing, image inverse column scrambling, image inverse row scrambling, circulation image inverse diffusing, image inverse column scrambling, multiple rounds of image inverse row scrambling, and a decrypted image is acquired. According to the invention, a feedback mechanism with the current image is introduced; the row (column) scrambling address code and the key matrix are dynamically changed in each round of encryption; experiments show that the method has the advantages of good encryption effect, high security and large key space, can resist selected plaintext attacks, known plaintext attacks and various statistical attacks.